I have never thought of 'losing the players' in the context that I believe it's often used on this board... which sounds to me like 'laying down', 'giving up', 'not playing hard'. I think that is a rare thing indeed and I'm not sure I've ever seen that.
To me.. and if I use that tern, "Losing The Players".. just to be clear.... I'm not saying the players have literally 'quit' on 'whomever'... what I mean is a lack of confidence in the system, the coach, both maybe... that manifests itself not so much in a conscious lack of effort but rather playing "hard" but without belief.
It's like anything else in life.. if you attempt 'anything' with the mental belief that 'it's not going to work' then odds are it probably isn't. Doesn't mean you aren't going full bore.